Retrospective simulation and analysis on "9·7" extraordinary rainstorm and flood in the Shenzhen City—Taking the Guanlan Watershed of the Longhua District as an example

Record-breaking rainstorm occurred in Shenzhen during the Sep 7th and 8th, 2023, which caused severe pluvial flooding, resulting in enormous damage in the watersheds including Longgang, Shenzhen and Guanlan watersheds. This research simulated the flooding of the Guanlan watershed in the Longhua District during the rainstorm, with the flooding analysis software, HydroMPM. Then, the situations of river channel overflow and the waterlogging in the urban areas were analyzed. The research results help revealing the causes of flooding disaster formation and thus providing reference to the decision-making on countermeasures.